ATEX
European Safety rating. ATEX products are rated for use in or around explosive atmospheres.

Bi-pin Bulb
A bulb with two contact pins that plug into a socket allowing easy replacement.

“Black Dot” Bulb
A Streamlight product. The black dot prevents stray light and gives the beam the ability to shine through dense mist, fog and smoke.

Beam Candlepower, aka Peak Beam Candlepower
Measurement of the brightest spot in a focused beam. An indication of the maximum intensity of the flashlight. The “hot spot” is equal in brightness to the number of “candles” required to produce the same illumination.

Candela
Also called “candle”. The unit of luminous intensity. One Candela is equivalent to 12.57 lumens. At one time it was equal to the light from one actual burning “standard candle”.

Candlepower
When referring to flashlights, candlepower is usually the same as beam candlepower.

CE
Flashlights carrying this symbol meet applicable European Community Directives, and can therefore be sold in Europe.

Dual Filament
This is a bulb that contains two filaments which enables users to instantly switch to the second filament when back-up lighting is needed.

EX
Signifies conformance to European Standards for use in potentially explosive atmospheres.

FM
Factory Mutual Research Corporation is a third party testing organization that approves products for use in specified hazardous locations.

HID (High-Intensity Discharge)
A type of lamp. These lamps include the types of electrical lights: mercury vapor, metal halide, high-pressure sodium, low-pressure sodium and less common, xenon short-arc lamps. The light-producing element of these lamp types is a well-stabilized arc discharge contained within a refractory envelope (arc tube) with wall loading in excess of 3 W/cm² (19.4 W/in.²). Compared to fluorescent and incandescent lamps, HID lamps produce a much larger quantity of light in a relatively small package.

Incandescent bulb
Incandescent lamps produce light by using electricity to heat a small coiled tungsten metal wire, enclosed within a glass “bulb” filled with special gases, to a high temperature – around 2,500 to 3,000 degrees Celsius – at which point the wire glows white-hot.

Incandescents produce a broad spectrum of light (including infrared) and can be made to have a high maximum lumen output, but they are comparatively less efficient users of power, and their lumen output level is effectively non-adjustable.

Intrinsically Safe
Not capable of igniting a flammable atmosphere under both normal and fault conditions.

Lamp Module
A lamp or bulb that has been integrated with the reflector to insure repeated performance and optimum focus. They are sold as a single unit.

LED (Light Emitting Diode)
A high-intensity “solid state” bulb which lasts up to 100000 hours. It is a semiconductor device that emits incoherent narrow-spectrum light when electrically biased in the forward direction. This effect is a form of electroluminescence.

Lumen
Unit of Luminance. As used in reference to flashlights, it refers to the total amount of light radiated by the bare bulb lamp, the LED, or the flashlight. Because this measurement does not consider the focusing efficiency of the reflector, it does not indicate how “bright” the focused beam will appear. A flood lamp with a very wide dim appearing pattern can have the same lumen rating as a very tightly focused intensely bright spot lamp assembly. Lumen rating cannot be converted to beam candlepower.

Lithium Batteries
Disposible batteries using lithium chemistry are gaining in popularity because of their light weight, high energy density, and shelf life of ten years.

NiCd (Nickel Cadmium)
The most common rechargeable battery used in rechargeable flashlights currently. It is a rugged rechargeable technology and provides the highest performance/cost ratio. They must be recycled at end of life.

Non-Incendive
Not capable of igniting a flammable atmosphere under normal operating conditions.

Non-Conductive
Will not conduct electricity. Flashlights made with non-conductive case materials protect against electric shock should the flashlight touch an electrical source.

O-Ring
Used as a gasket to seal the flashlight case against dust and moisture.